Unhealthy diets and a lack of exercise in children are leading to metabolic disorders in adults. This dissertation characterized effects of early-life experiences (phenotypic plasticity) on adult activity levels by altering the diet and/or exercise of juvenile mice. Subjects were from a selection experiment in which four replicate lines of High Runner (HR) mice evolved to run 2.5-3-fold more wheel revolutions per day than those from four non-selected Control (C) lines. Expectations were that 1) early-life experiences would have long-lasting effects into adulthood, 2) early-life factors would have interactive effects, and 3) genotype-by-environment interactions would occur). Chapter 1 considered effects of early-life high fat, high sugar diet and/or exercise on adult physical activity. Juvenile mice were exposed to 3 weeks of Western diet (WD) and/or wheel access, beginning at weaning, followed by an 8-week washout period (~6 human years). In adults, early exercise increased wheel running of C but not HR mice, decreased anxiety-like behavior and heart ventricle mass, but increased fasted blood glucose levels, triceps surae, subdermal fat pad, and brain masses. In contrast, early-life WD increased adult wheel running of HR but not C mice. Chapter 2 exposed mice to similar early-life treatments, except WD was replaced with fructose in drinking water to assess its potential to suppress activity levels acutely and into adulthood after a 23-week washout period. One HR and one C line were used. As in Chapter 1, early exercise increased adult running, but also decreased adult fat mass. Early-life fructose increased fat mass acutely but had inconsistent effects on wheel running and cage activity, with no long-lasting effects into adulthood. Chapter 3 was a cross-fostering experiment designed to test the importance of the early postnatal maternal environment in the development of the HR phenotype. Fostering C pups to HR dams did not increase the wheel running of C adults, nor did fostering HR pups to C dams suppress running of HR adults. These studies demonstrate that early-life experiences can have both acute and long-lasting effects on various traits, including physical activity, and that those effects interact with genetic background.

This dissertation considers the problem of learning and teaching Boolean task specifications, such as automata, using demonstrations. The resulting framework bridges grammatical inference and maximum-entropy inverse reinforcement learning with applications in human-robot interaction, formal synthesis, and multi-task reinforcement learning.

In the context of inverse reinforcement learning, Boolean task specifications are a class of sparse memory augmented rewards with explicit support for temporal and Boolean composition. These properties make task specifications immune to certain classes of reward hacking bugs that emerge from ad-hoc composition or perturbations to the dynamics. Unfortunately, the discrete nature of task specifications combined with an a-priori ignorance of what historical features are needed to encode the demonstrated task make existing approaches to learning rewards from demonstrations inapplicable.

In the context of specification mining and grammatical inference, demonstrations provide an ergonomic and sample efficient means to communicate formal languages and specifications. For example, this dissertation enables a user to partially specify the desired behavior of a system as example demonstrations and then find an automata or program that explains the user's behavior. Conversely, by synthesizing pedagogic demonstrations, this dissertation enables communicating the nuances of a specification that may be hard to intuit from a formal description.

In either case, this thesis contributes a collection of algorithms and theoretical machinery for systematically mitigating combinatorial explosions inherent in (1) finding specifications that explain an agent's behavior (2) finding pedagogic demonstrations that help humans infer the specification and (3) robustly predicting the behavior of an agent adhering to a specification.

The Larsen group focuses on accessing small molecules through one-step multi-component coupling reactions from inexpensive starting materials and a catalyst source. To this end, we have developed a solvent-free catalytic method to access various substituted 2-(2'-pyridyl)quinoline compounds in one step directly from inexpensive and commercially available materials. Purification is simple and is accomplished with the use of a short basic alumina plug and diethyl ether as the eluent. Current published methods to access these targets are plagued with lengthy multi-step reactions, hazardous reagents, and/or the wasteful use of solvents and other materials for purification purposes. In vitro studies of two substituted 2-(2'-pyridyl)quinoline compounds revealed cytotoxic activities in the A549 lung cancer cell line. In addition to the synthesis of various bidentate substituted 2-(2'-pyridyl)quinoline ligands, the neutral 5-coordinate gold(III) complexes of 6-phenyl-2-(2'-pyridyl)quinolines substituted at position 6 of the quinoline ring with fluorine, methyl, methoxy, and phenyl groups were also achieved. The x-ray crystallographic data revealed that the neutral complexes have distorted square pyramidal geometries. Furthermore, the cationic gold(III) complex of a 6-phenyl-2-(2'-pyridyl)quinoline with a methoxy moiety at position 6 of the quinoline ring was also synthesized with a tetrafluoroborate counter anion. The x-ray structure of this cationic complex revealed its distorted square planar geometry.

Insect communities vary seasonally with changing climatic conditions and related changes in resource availability, strength of competition, or pressure by natural antagonists. But seasonal dynamics, particularly in tropical mountain ecosystems, are not well understood. We monitored cavity-nesting Hymenoptera communities on Mt. Kilimanjaro, Tanzania, to analyse temporal patterns of nest-building activity, ecological rates, and life-history traits in relation to seasonal climatic variation and elevation. We installed trap nests on 25 study sites in natural and disturbed habitat types covering the colline (<1,300 m) and submontane zones (≥1,300 m a.s.l). We analysed patterns of seasonality in the cavity-nesting ecology of Hymenoptera at three different trophic levels –bees, caterpillar-hunting wasps and spider-hunting wasps– over a complete annual period, covering two rainy and two dry seasons. Nest-building activity showed strong seasonal trends in all three investigated trophic levels and peaked at the end of the short rainy season at low elevations. Nest-building activity was considerably higher and seasonal trends were better synchronised between the different trophic levels in the colline zone at low elevations. We also detected seasonal patterns for parasitism and natural mortality rates, sex ratio, and development time, which varied with trophic level and between elevation levels. Climate and flower abundance were important predictors for seasonal patterns in nest-building activity, ecological rates and life-history traits. These results reveal that seasonal trends in nest-building activity of lowland Hymenoptera seem to be linked to changes in climate and resource availability that reflect the seasonal patterns in plant growth and flowering documented in lowland savanna ecosystems. Higher resource availability also increased the sex ratio in bees towards the more costly females and enhanced their survival rates. These spatiotemporal links between climate, resources, ecological rates, and life-history traits indicate high sensitivity of plant-host-antagonist interactions to environmental changes.

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